T-Mobile has been the fourth most popular network in the U.S. for quite some time. They have big plans to get to the front of the pack, though, in 2013, and it seems like little by little this is coming into place.

They've been doing a lot to increase their current network infrastructure with a $4 billion modernization program. This program is aimed at enhancing the network's existing cell sites and improving HSPA+ signal strength in different areas all over the country.

Also, T-Mobile is working on building out its LTE network; to which, the addition of MetroPCS, will definitely help. This LTE expansion will not cover all devices though. As Engadget reports, T-Mobile will be restricting its own LTE goodness to high-end devices for the time being. Included in that category are devices like the Samsung Galaxy Note II and yes, the BlackBerry Z10. The Z will be making its debut on the network at the end of the month, and yes, we are still waiting for an official date from Magenta.

T-Mobile's strategy to restrict LTE, for the time being, to a few select devices shows how much they really believe BlackBerry 10 has a shot. They could've opted to go with the non-LTE BlackBerry Z10STL100-1, an HSPA+ device that does the job on a lower network speed. Instead, they waited it out and invested in the same device AT&T will be introducing, the Liverpool STL100-3, an LTE-ready device.